Ionizer

ABSTRACT

An ionizer is provided with an ion-producing means in the form of a carbon electrode to which a high source of DC potential is applied for generating a substantial amount of ions of the same polarity as that of the applied potential by corona discharge. In an illustrated application, the carbon ion-producing electrode is mounted on a fan of an air ionizer for rotation therewith, for simultaneously generating air ions and rapidly dispensing the ions in the air stream of the fan, which may be directed axially or radially therefrom.

United States Patent [1 1 Ignatjev 1 IONIZER [76] Inventor: VladimirIgnatjev, 39 Ledgewood Dr., Norwalk, Conn. 06850 22 Filed: Nov. 2, 1973[21] Appl.No.:412,l51

[52] US. Cl 250/324, 317/4, 250/423 [51] Int. Cl. H05b 3/00 [58] Fieldof Search 250/324, 325, 326, 423; 317/4 [56] References Cited UNITEDSTATES PATENTS 1,984,159 12/1934 Schwedenberg et al 317/4 2,949,5508/1960 Brown 317/4 3,085,749 4/1963 Schweitzer 317/4 3,183,352 5/1965Brandt et a1. 250/324 3,582,711 6/1971 Jahnke 317/4 3,624,448 11/1971Saurenman et a1. 317/4 1 Mar. 25, 1975 6/1970 Edwards 317/4 12/1973Kamogawa et al. 250/324 Primary Examiner-James W. Lawrence AssistantExaminer-B. C. Anderson Attorney, Agent, or Firm-Joseph Levinson, Esq.

[57] ABSTRACT An ionizer is provided with an i m-producing means in theform of a carbon electrode to which a high source ol DC potential isapplied for generating a substantial amount of ions of the same polarityas that of the applied potential by corona discharge. In an illustratedapplication, the carbon ion-producing electrode is mounted on a fan ofan air ionizer for rotation therewith, for simultaneously generating airions and rapidly dispensing the ions in the air stream of the fan, whichmay be directed axially or radially therefrom.

5 Claims, 7 Drawing Figures KTENTED MAR 2 51975 snmlpfz IONIZER Thisinvention relates to an ionizer for generating ions by corona discharge,and more particularly in one form thereof to an air ionizer forgenerating and dispensing ionized air.

Ion generation is becoming increasingly important for a number ofapplications. Some industries are plagued by static charge that attractsdust and dirt and causes self-attraction of charged particles, making itdifficult to operate certain types of equipment, for example, that whichis utilized to stack plastic bags, handle webs of plastic or paper, andother materialhandling functions. Many electrical apparatus, includingcomputers, can be affected by electrostatic charge on the surface of thewiring or on isolated chassis parts. If the static charge build-up islarge enough to produce a spark, the result could be as little as anannoying personal shock, or as serious as an explosion. In anotherapplication, ions are generated to place a charge on photo-sensitivepaper or other such materials in the document-reproduction field.Another important area which is under investigation is the effect of airions on plants and living organisms, including their effect on humans.The results of such investigations tend to show that a preponderance ofpositive air ions in the air has a detrimental effect on most humans,causing headaches, nervousness, and a generally reduced capability ofthe thinking processes to function normally. On the other hand, anexcess of negative air ions appears to favorably influence the centralnervous system, lower blood pressure, reduce the tendency to fatigue,increase the capacity to concentrate, and produce an over-all calmingeffect of wellbeing.

A number of approaches have been taken for generating ions which operateon the corona discharge principle, utilizing metallic needles or wire ofvery small diameter. Among the problems which exist with known systemsis the lack of adequate generation of ions in a small space, as well astheir speed of removal. Since the air ions have a relatively short life,from milliseconds to 30 seconds, they must be generated in adequatequantity and dispensed promptly in order to derive any benefittherefrom. In corona discharge systems ion density is also a function ofthe speed of removal from the electrode. Another problem encountered incorona discharge devices is the generation of toxic ozone and nitrousoxides, which are not only undesirable, but which cannot be tolerated inlarge quantities.

Accordingly, it is an object of this invention to pro vide an ionizerfor generating ions in substantial quantities in a small space wileavoiding substantial production of ozone and other toxic gases.

A further object of this invention is to provide a new and novelion-producing means which is incorporated with an ion-dispensing meansfor simultaneously gener ating and dispensing ions to the surroundingarea.

SUMMARY OF THE INVENTION In carrying out this invention in .oneillustrative embodiment thereof, an ion-producing means in the form ofacarbon electrode is provided, having a high source of DC potentialapplied thereto for generating a substantial amount of ions of the samepolarity as that of the applied potential by corona discharge. Theionproducing means may be mounted on a fan of an air- 2 ionizer forrotation therewith for simultaneously generating and rapidly dispensingthe ions generated thereby in the air stream 'of the fan, which may bedirected axially or radially therefrom.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front elevation, partly insection, of one form of air ionizer embodied in the present invention.

FIG. 2 is a cross-sectional view of the fan shown in FIG. 1. FIG. 3 is atop sectional view of the fan shown in FIG. 2.

FIG. 4 is an enlarged portion of one type of electrode which may beemployed in the present invention.

FIG. 5 is an enlarged view of another type of electrode which may beemployed in the present invention.

FIG. 6 is a front view of another type of fan which may be employed inthe present invention.

FIG. 7 is a top view of FIG. 6.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Ions are classified accordingto size as small, medium or large, and have a lifetime of millisecondsto thirty seconds, depending on their size and polarity. Positive ionsare used for charge reversal in copying processes, and are consideredfavorable for plant life. Negative ions are used for charging zinc oxidepaper in copying processes, and are considered favorable for animals,and humans. The generation of positive ions by corona discharge isprimarily a gas-phase phenomenon, and is not highly sensitive to thematerial used for the electrode generating the ions or the surfacecondition of the electrode. However, the generation of negative ions bycorona discharge involves both the gas-phase phenomenon and the electronemission properties of the electrode material utilized and its surfacecondition. Extensive tests have shown that the dominant ions in air atatmospheric pressure for negative corona are CO ions. The presentinvention in its broadest scope utilizes this fact by employing aconductive carbon electrode which, as used herein, would include withinits scope conductive graphite. The carbon material utilized as a coronadischarge electrode has two functions. The first is to supply carbon forthe production of CO ions, and second to act as a reducing agent for Oand NO ions. An example of one of the reactions is as follows:

0 CO CO 0 One preferred form of carbon electrode is shown in FIG. 4, andidentified with the reference numeral 50. The carbon electrode 50 is inthe form ofa stranded filament which is cut to the length of A to l inchwhich, when under great magnification, resembles at one end thereof theappearance of a brush. A high source of DC potential, on the order of10,000 to 30,000 volts, is applied to the electrode 50 to produce acorona discharge along the surface and at the ends of the strandedfilament 50. The polarity of the ions generated is the same as thepolarity of the DC potential applied thereto. With the configuration ofthe carbon electrode 50 as shown in FIG. 4, hundreds of coronadischarges occur on the ends of the filament to produce or generateions. Since the charge of the ions so generated has the same polarity asthe filament ends, the ions so generated are repelled, dispensing theminto the outer atmosphere surrounding the electrode 50. The generationof the many corona-producing points of the electrode 50 propels the ionsrapidly outward. The carbon electrode may also be in the form of astranded filament 57, as shown in FIG. 5. In this case the many strandsofthe filament 57 generate ions along the surface thereof, of the samepolarity asthat of the high potential applied thereto. Although theinvention is not considered limited to a specific type of carbonelectrode, one type which has been found suitable for the presentapplication is produced by Union Carbide Corporation having a diameterof 0.04 in. consisting of five plies with 480 filaments per ply.Although the aforesaid carbon electrode may be used for generating ionsfor many applications, it is further described herein with reference toan air ionizer utilizing a rotating fan for dispensing the ions. Itshould be appreciated, however, that in the application described. othertypes of electrodes, for example metallic electrodes, may also beutilized in that application, and the type ofelectrode used will dependon the particular requirements of any specific application requiring thegeneration of ions.

Referring now to FIG. 1, one form of air ionizer is shown, having anenclosure 10, a bottom panel 12, a divider 14, side openings 15, and aclosure 16 in the form of a filter which rests on a ledge 18 in theenclosure 10. A motor 20, mounted on the bottom panel 12, has a rotatingmotor shaft 22 which drives a fan shaft 28 via a cylindrical coupler 24having an H-shaped cross-section. A cage-type fan 30 is mounted forrota"- tion on the fan shaft 28 by the motor 20. The motor is spacedfrom the divider 14 by a flanged spacer26. A doughnut-shaped powersupply 40 which supplies a high DC potential, on the order of 10,000 to30,000 volts, is grounded on one terminal thereof, and the otherterminal is connected via conductor 38 to a reflector electrode 34mounted in the upper'flange'ofthe flanged spacer 26. This electrode iscoupled via conductor 36 to metal bearings 32 which apply the source ofpotential 40 to the fan shaft 28. It will be understood that other formsof means for applying the potential to the shaft 28 may be utilized; forexample, a brush and slip-ring arrangement could be used.

The stationary grid 42 is provided in front. of the openings 15 in theenclosure 10, which is coupled to the source of potential 40 through apotentiometer 44 for controlling the potential on the grid. The grid 42can be utilized to control or regulate the flow of ions from theionizer.

As will best be seen in FIGS. 2, 3 and 4, corona discharge electrodes 50are mounted on an insulated wire 55, which is mounted on the fan bladesof the fan 30. The conductor 55 is conductively coupled to the fan shaft28 by insulated conductor 52. As will be seen in FIG. 4, the electrode50 is mounted to the insulated conductor 55 in an area which may besurrounded by a sphere of insulated material 56 to create turbulence ofthe air to help move the ions away from the electrode 50 as they aregenerated. As is illustrated in FIG. 3, a plurality of electrodes 50 maybe spaced within the cage-type fan.

In the preferred form, the electrode 50 would be made of a conductivecarbon as described above, which provides hundreds of ion-producingpoints. However, it will be apparent to those skilled in the artutilized if desired. 7

In operation, and assuming that it is desired to generate negative ions,the ion-producing electrodes 50 are coupled to the fan shaft 28 byinsulating conductors 52. The fan shaft 28, which is rotated by themotor 20 via the motor shaft 22 and the coupler 24, has a source of highnegative potential applied therethrough through the bearings 32 whichare coupled via line 36 to reflector electrode 34 and to the negativeterminal of the power supply 40 by conductor 38. The high negativevoltage which is transmitted to the electrodes 50 produces a largesupply ofnegative ions. The movement of the fan, along with theplurality of electrodes spaced within the fan blades, moves a stream ofair, carrying the ions in a radial direction out through the openings 15in the enclosure 10, dispersing them to the areas desired. Theconstruction illustrated provides several important features. With theexception of the conductors and metal shaft, all other portions of thesystem are made of insulating material, which isolates the groundedmotor and power supply from the fan. Since the fan shaft 28 supplies thesource of potential to the electrodes 50 and the ions generated are thesame polarity as the potential applied to the electrodes, the shaftitself acts as a reflector, sending the ions away from the shaft. Areflector electrode 34 is also provided between the grounded motor andpower supply, and electrodes 50, which reflects the ions and preventsthem from being deflected toward the grounded motor and power supply. Alarge amount of ions are generated because each channel of the radialfan can carry an ion-producing electrode. As was stated previously, theamount of the ions produced is limited by the speed of the ion removalfrom the ion-producing electrodes 50. By combining the electrodes withthe fan, rapid removal is achieved, since the ions generated aredispensed simultaneously by the movement of electrodes with the fan. Thesphere 56 partially surrounding the electrodes 50 also createsturbulence, moving the ions away from the electrodes. The system is alsomade compact by the combination of the ion production and their removalmeans into a single integral unit. It will also be noted that, unlikemany other systems, a grounded electrode in close proximity to theionproducing electrode is eliminated in the present system. The presentsystem avoids this by using a high voltage with one terminal to thepower supply grounded, and the exposed area of the charge-carrying partsis kept to a minimum. The maintaining of the high voltage-carryingsurface at a minimum reduces the pro duction of ozone and other toxicgases. Also, in using a carbon electrode, which is the preferred form,the carbon combines with the oxygen to produce CO and prevents theformation of ozone. As was pointed out earlier, the system does notrequire an opposite field electrode, which also holds down gasproduction. Then, too, the high voltage-carrying surfaces are maintainedat a minimum.

FIG. 5 shows another type of corona discharge electrode 57, which may beutilized in the form of a metal wire, or preferably conductive carbon instranded filament form. The electrode 57 is mounted on the fan blade,similarly to the wire 55 in FIG. 4, but with the surface being exposedand the high voltage applied thereto for creating corona discharge. Theelectrode will be on the order of 0.002 to 0.004 in. for metal and 0.04in. for the carbon type. The conductive carbon stranded electrode ispreferred since its surface consists of hundreds of tiny filaments whichgenerate more ions than the similar wire filament. Then, too, because ofthe larger surface area and with the high negative potential on thestranded electrode, in the case of negative ion generation, the ions arestrongly repelled from the surface of electrode 57.

FIGS. 6 and 7 illustrate the combined ion-producing electrodes and fanin the form in which the air stream is propelled axially instead ofradially, as illustrated in FIG. 1. The fan 60 has a plurality ofelectrodes 50, for example like those shown in FIG. 4. positionedbetween each of the blades are shown, any suitable plurality may beprovided with the electrodes positioned therebetween, and the shape maytake many forms. The high voltage may be coupled to the electrodes,utilizing a power supply and the means shown in FIG. 1. Corona dischargeelectrodes such as shown in FIG. 5 may also be utilized in place of theelectrodes shown by mounting them on the blades to extend between theblades and rotate therewith. The operation of the fans of FIG. 1 andFIG. 7 is the same, except that in the case of FIG. 1 the stream of airwith the ions therein is generated radially, whereas the stream of airwith ions is generated axially by the fan of FIG. 6. The same objectivesare achieved by the two types of fan generating the air stream, which isto generate a large amount of ions in a small space, with the negligibleproduction of toxic gases, and deliver the ions quickly to the desiredarea. With respect to the embodiment of FIG. 6, the compactness isachieved in the same manner as shown in FIG. I by a combination of ionproduction and the air-moving means into an integral ion-generating fan.

Since other modifications and changes, varied to fit particularoperating requirements and environments, will be apparent to thoseskilled in the art, the invention is not considered limited to theexamples chosen for purposes of disclosure, and covers all changes andmodifications which do not constitute departures from the true spiritand scope of this invention.

I claim:

I. An air ionizer for generating and dispersing ionized air, comprising,in combination,

a. a radial fan having a fan shaft,

b. a rotating cage-type fan blade means mounted on said fan shaft forrapidly moving a stream of air in a radial direction therefrom on therotation of said fan,

c. ion-producing electrode means mounted on and positioned within saidcage type fan blade means in conductive contact with said fan shaft forsimulta neously generating air ions and rapidly dispersing said ions bysaid stream of air into the radial space surrounding said fan,

d. a source of high DC. potential, and

e. means for conductively coupling said source of high DC. potential tosaid fan shaft thereby applying said source of high DC. potential tosaid ionproducing electrode means whereby air ions are generated by saidion-producing electrode means by corona discharge.

2. The air ionizer set forth in claim 1 wherein said ion producingelectrode means is comprised of conductive carbon electrodes.

3. The air ionizer set forth in claim 2 wherein said conductive carbonelectrodes are in the form of stranded filaments of conductive carbon.

4. The air ionizer set forth in claim 1 having a. a motor and a motorshaft driven thereby,

b. insulated coupling means for coupling said motor shaft to said fanshaft whereby said motor drives said fan shaft, and

c. a reflector electrode mounted between said motor and saidion-producing electrode means and coupled to said source of high DC.potential of the same polarity applied to said ion-producing electrodemeans, whereby said reflector electrode repels air ions generated bysaid ion-producing electrode means.

5. An ionizer for generating ions by corona discharge comprising a. anion-producing electrode means comprising conductive carbon in the formof a plurality of stranded filaments, each filament having an extremelysmall diameter in the micron range,

b. a source of high voltage,

c. means for applying said source of high voltage to said ion-producingelectrode means for generating a substantial amount of ions by coronadischarge, and

d. fan means for moving a stream of air over said ion producingelectrode means, thereby rapidly dispensing the ions generated by saidion producing electrode means.

1. An air ionizer for generating and dispersing ionized air, comprising,in combination, a. a radial fan having a fan shaft, b. a rotatingcage-type fan blade means mounted on said fan shaft for rapidly moving astream of air in a radial direction therefrom on the rotation of saidfan, c. ion-producing electrode means mounted on and positioned withinsaid cage type fan blade means in conductive contact with said fan shaftfor simultaneously generating air ions and rapidly dispersing said ionsby said stream of air into the radial space surrounding said fan, d. asource of high D.C. potential, and e. means for conductively couplingsaid source of high D.C. potential to said fan shaft thereby applyingsaid source of high D.C. potential to said ion-producing electrode meanswhereby air ions are generated by said ion-producing electrode means bycorona discharge.
 2. The air ionizer set forth in claim 1 wherein saidion producing electrode means is comprised of conductive carbonelectrodes.
 3. The air ionizer set forth in claim 2 wherein saidconductive carbon electrodes are in the form of stranded filaments ofconductive carbon.
 4. The air ionizer set forth in claim 1 having a. amotor and a motor shaft driven thereby, b. insulated coupling means forcoupling said motor shaft to said fan shaft whereby said motor drivessaid fan shaft, and c. a reflector electrode mounted between said motorand said ion-producing electrode means and coupled to said source ofhigh D.C. potential of the same polarity applied to said ion-producingelectrode means, whereby said reflector electrode repels air ionsgenerated by said ion-producing electrode means.
 5. An ionizer forgenerating ions by corona discharge comprising a. an ion-producingelectrode means comprising conductive carbon in the form of a pluralityof stranded filaments, each filament having an extremely small diameterin the micron range, b. a source of high voltage, c. means for applyingsaid source of high voltage to said ion-producing electrode means forgenerating a substantial amount of ions by corona discharge, and d. fanmeans for moving a stream of air over said ion producing electrodemeans, thereby rapidly dispensing the ions generated by said ionproducing electrode means.